Racket with replaceable string frame

ABSTRACT

A racket for use in playing tennis or similar games, the racket having a removable playing surface. The racket-frame is provided with an opening, and a removable string-frame is provided to carry the playing surface. The string-frame can be easily removed from the racket-frame, and another string-frame with a new playing surface can be inserted into the racket-frame and secured by fastening means.

United States Patent Edlefsen [54] RACKET WITH'REPLACEABLE STRING FRAME[72] Inventor: Thomas B. Edlefsen, 1315 N. June Street, Hollywood,Calif. 90028 [22] Filed: March 29, 1971 [21] Appl. No.2 129,059

[52] US. Cl. ..273/73 L [51] Int. Cl. ..A63b 51/00 [58] Field of Search..273/73 R, 73 C, 73 D, 73 E,

. 273/73 G, 73 H, 73 J, 73 K [56] References Cited I UNITED STATESPATENTS 240,183 4/1881 Richardson, ..273 73 E 1,558,507 10 1925 Ryder.;.273/73 13 2,054,444 3/1936 Rauch et a]. .....273 73 E 2,224,567 121940 Reaeh ..273/73 c 2,369,145 2/1945 1 .....273 73 R 2,969,984 1 /1961Presnick ..273 73 R 1151 3,707,288 [4 1 Dec. 26,1972

FOREIGN PATENTS OR APPLICATIONS 208,945 l/l957 Australia ..273/73 R639,932 3/1928 France ..273/73 D 1,503,812 10/1967 France ..273/73 C2,000,606 9/1969 France ..273/73 R 189,874 12/1922 Great Britain 273/73C 227,012 l/l925 Great Britain 273/73 D 712,224 7/1954 Great Britain....273/73 J Primary Examiner-Richard C. Pinkham Assistant Examiner-RichardJ. Apley Attorney-Jones & Thomas 57 ABSTRACT A racket for use in playingtennis or similar games, the

racket having a removable playing surface. The

racket-frame is provided with an opening, and a removable string-frameis provided to carry the playing surface.' The string-frame can beeasily removed from the racket-frame, and another string-frame with anew playing surface can be inserted into" the racketframe and secured byfastening means.

5 Claims, 10 Drawing Figures PATENTED um 25 1912 sum 2 OF 2 mvsmonThomas B.Edlefsen W" flame-4 ATTORNEYS BACKGROUND'OF THE INVENTION Thisinvention relates to tennis rackets and similar rackets for use insporting-events, and is more particularly concerned with a racket inwhich the playing surface is readily removable and replaceable byanother playing surface. 1

Tennis rackets, and the like, with removable strings have been known inthe past, but prior artrackets have usually had such a complexarrangement to allow a string-frame to be inserted into the racket-framethat the entire racket became very unwieldy.

SUMMARY OF THE INVENTION The present invention overcomes the above-menqtioned and otherdifficulties by providing a substantially conventionaltennis racket in which the racketframe is open to receive a string-framewhich is inserted into the racket-frame. Means are also provided toretain the string-frame within the racket-frame; and when thestring-frame is inserted into the racket-frame the entire racket isrenderedunitary with a small number of parts so that the racket remainslight in weight and well balanced. Further, the racket of the presentinvention is so constructed that the ordinary tennis player can exchangethe string-frame with relative case.

These and other features and advantages of the present invention willbecome apparent upon a consideration of the following specification whentaken in conjunction with-the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top-plan view of a racketembodying one form of the present invention;

FIG. 2 is a partial front-elevational view of the racket shown in FIG.1, and showing the string-frame partially removed from the racket-frame;

FIG. 3 is an enlarged cross-sectional view taken substantially along theline 33 in FIG. 1;

FIG. 4 is an enlarged cross-sectional view taken substantiallyalong theline4-4 in FIG. 1; y FIG. 5 is an enlarged cross-sectional view takensubstantially along the line 5-5 in FIG. 1;

FIG. 6 is an enlarged cross-sectional view taken substantially along theline 66 in FIG. 1;

FIG. 7 is a view similar to FIG. 1 but showing a modified form of thepresentinvention;

FIG. 8 is an exploded front-elevational view of the racket shown in FIG.7;

FIG. 9 is an enlarged cross-sectional view taken sub- Y stantially alongthe line 99 in FIG. 7; and

FIG. 10 is a cross-sectional view taken substantially along the line1010 in FIG. 9.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now more particularlyto the drawings, and

- to that embodiment shown in FIGS. 1 through 6 in the accompanyingdrawings, it will be seen that a tennis racket assembly 8 is providedwhich includes a handle or string-frame support 9 and a string-frame 15.The string-frame support includes an elliptically shaped or ovalracket-frame 10 at one end, and a central shank 1 1 terminating ina handgrip 12 at its other end. The racket-frame 10 and the shank 11 are hereshown as formed integrally, but it will be understood by those skilledin the art that the two pieces can be formed separately and joinedtogether by numerous known means.

The racket-frame 10 has'the usual oval configuration, and theracket-frame 10 is bifurcated along'approximately one half the portionthereof remote from the shank ll to form opening or slot 14 and isprovided with an inwardly facing arcuate slot or channel 16 along itsremaining internal surface adjacent shank 11 into which the string-frame15 can be removed or inserted. The opening 14 extends substantiallyhalfway around the end of the racket-frame 10 that is most remote fromthe shank 11 and. channel 16 is aligned with opening 14. I

The inwardly opening channel 16 is provided, substantially along thecenterline of the racket, with an aligning hole l8 to receive analigning peg 19 that is formed integrally with the string-frame 15.

It will be seen that, in the vicinity of the opening 14, theracket-frame 10 is reduced to a pair of flat strips 20 and 21. Thesestrips are, however, well supported when a string-frame 15 is placedwithin the racket-frame 10 as will be understood-more fully hereinafter.

Referring now particularly to the string-frame 15, it will be seen thatthe half of the string frame 15 that corresponds with the opening 14 ofthe racket-frame 10 is substantially the same width as the strips 20 and21, and is provided .with an outwardly facing peripheral groove 22 toreceive the strings 24. By this means the strings 24 are recessed withinthe racket to prevent undue abrasion of the strings.

Substantially along the centerline of the racket, and at the end moreremote from the shank ll, fastening means are provided which comprisealigned holes 25 and 26 in the strips 20 and 21, respectively, of theracket-frame l0, and a hole 28 in. the string-frame 15. It will be seenin FIGS that the hole 25 and the hole 28 are sufficiently large toreceive the shank 29 of a screw 30 while the hole 26 is threaded toreceive the threaded end of the screw 30. Thus, the string-frame 15 canbe placed within the racket-frame 10, and the screw 30 can be passedthrough the holes 25 and 28 and then threadedly engaged in the hole 26to secure or clamp together the entire outer end of the string-frame 15.The string-frame 15 is under cut on opposite sides thereof to formshoulders 31 so that the portion of the string-frame 15 that is to beadjacent to the shank l l is sufficiently small to be received withinthe channel 16 of the racket-frame 10. Again, this portion of thestring-frame 15 is provided with an outwardly facing channel 32 so thatthe strings 24 will not interfere with the string-frames fittingproperly within the channel 16.

From the foregoing it should now be readily seen that a string-frame 15can be inserted through the opening 14 in the racket-frame 10 until thealigning peg 19 is received within the hole 18. This assures precisealignment ofthe string-frame 15 with the racket-frame 10; then, thescrew 30 will be passed through the holes 25 and 28 which should now bealigned, and the screw 30 is rotated to engage the threaded hole 26 inthe strip 21 of the racket-frame 10. Once the screw 30 is tightened,

remove and insert the screw so that the player need have no toolsavailable in order to exchange the stringframe 15 in his racket.

Attention is now directed to FIGS. 7 through 10 of the drawings whereinanother embodiment of the racket is shown. It will be seen in FIG. 7that the racket includes a racket-frame 110, a shank 111 connectedthereto, and a handle 112 at the end of the shank 111. The racket-frame1 10 is provided with an opening 114 through which a string-frame 115 isinserted.

- In this embodiment, the opening 114 in the racketframe 110 is formedby making the periphery'of the racket-frame 110 inan L-shape incross-section, as best seen in FIG. 9, so that there is a -lower flange121 while the upper side of the racket-frame 1 10 is open.

As aretaining means to holdthe string-frame. 115 in the racket-frame 110, there is provided'a snap-ring 130 to be received within a peripheralgroove125 in the rackebframe 110. The snap-ring 130 is of asubstantially conventional variety in which the snap-ring 130 is made ofa resilient material such'as spring steel and is biased to spring open.The ends of the snap-ring 130 are provided with holes 129 so that a toolcan be inserted into the holes to'compress the snap-ring 130 and removethe snap ring from the groove 125 in order to remove the string-frame115 from the racket-frame The string-frame 1 in this embodiment has auniform perimeter which is provided with an outwardly facing groove 22to allow the strings 124 to be recessed so that they will not interferewith the string-frames entering the racket-frame 110.

1n the event the string-frame 115 is made of a relatively hard materialit is possible that the corners of string-holes 140 may be sharp enoughto cut the strings and thereby greatly reduce the life of the strings inthe string-frame 115. To diminish this possibility, bushings 141 areplaced within the holes 140 and provide blunt corners 142 to preventcutting the strings 124. The bushings 141 may be made of a plasticmaterial, or the like, so that the bushing will be relatively soft andunable to cut or otherwise damage the strings 124.,

From the foregoing it will be seen that in this embodiment astring-frame l 15 can be slipped through the opening 114 into theracket-framev 110. Since both the string-frame 115 and the racket-frame110 are of an oval or otherwise non-circular configuration, there islittle danger that the string-frame 115 will be misaligned with theracket-frame 110. When the string frame 115 is sufficiently well seatedon the flange 121 v 4 readily exchanged by the ordinary player. Very fewtools are required to make the exchange and extremely little mechanicalskill is required to exchange thestring-frame. Accordingly, a 'playercan "have one racket but carry several pre-strung string-frames. If thestrings in the racket become too severely worn, or break, the entirestring-frame can be very quickly removed, and another string-frameinserted so that play with the racket may be resumed.

- While this invention has been described in detail with r particularreference to preferred embodiments thereof,

I with said slot along the remaining portion thereof, an

of the racket-frame 110, the snap-ring 130 can be racket including ashank, a handle at one end of said shank and a racket-frame at theopposite end of said shank and fixed thereto, said racket-frame beingadapted to-hold'the playing surface, a string-frame carrying the playingsurface, said string frame having substantiallythe same configuration asthe racket-frame, said racket-frame having a continuous periphery, aportion of the periphery of said racket-frame defining an inwardlyfacing channel, said racket-frame having an opening therein to receivethe string-frame, said channel being opposite said opening and alignedtherewith so that said string-frame is received within said opening andwithin said channel, and retaining means to secure the string-framewithin the racket-frame.

2. A racket according to claim 1 wherein said opening to receive thestring-frame is in the end of the racket-frame that is opposite from theshank, said opening extending substantially halfway around theracket-frame.

3. A racket according to claim 2 wherein said racketframe includesstrips defining the opening, said stringframe substantially filling theopening and said retaining means acting to secure the string-frame tothe strips. g

4. A racket according to claim 3 and further including an aligning pinextending from the string-frame, 7 said racket-frame having an aligninghole located along the centerline of the said shank and adapted toreceive the aligning pin.

5. A tennis racket assembly comprising a stringframe support including ashank, a handle grip at one end of saidshank, and a generally ovalracketframe at the other end of said shank, saidracket frame beingbifurcated along approximately the one-half portion thereof remote fromsaid shank to form a slot and formed with an inwardly facing channel inalignment aligning hole defined in said racket frame adjacent saidshank, a generally oval string frame generally of a size and shapecorresponding to the size and shape of said racket frame and of athickness sufficient to be'snugly received in the slot and channel ofsaid racket frame, said string frame being of smaller width in theportion thereof adjacent said shank and including outwardly extendingshoulders at the junction of the slot and channel of said racket frame,said string frame including an aligning peg projecting therefrom andreceived in the aligning hole of said racket frame, and fastening3,707,288 6 means positioned at the end of said racket frame remote fromsaid shank for clamping said racket frame against said string frame.

2157 IOMHZ 0H0

1. A racket having a replaceable playing surface, said racket includinga shank, a handle at one end of said shank and a racket-frame at theopposite end of said shank and fixed thereto, said racket-frame beingadapted to hold the playing surface, a string-frame carrying the playingsurface, said string-frame having substantially the same configurationas the racket-frame, said racket-frame having a continuous periphery, aportion of the periphery of sAid racket-frame defining an inwardlyfacing channel, said racket-frame having an opening therein to receivethe string-frame, said channel being opposite said opening and alignedtherewith so that said string-frame is received within said opening andwithin said channel, and retaining means to secure the string-framewithin the racket-frame.
 2. A racket according to claim 1 wherein saidopening to receive the string-frame is in the end of the racket-framethat is opposite from the shank, said opening extending substantiallyhalfway around the racket-frame.
 3. A racket according to claim 2wherein said racket-frame includes strips defining the opening, saidstring-frame substantially filling the opening and said retaining meansacting to secure the string-frame to the strips.
 4. A racket accordingto claim 3 and further including an aligning pin extending from thestring-frame, said racket-frame having an aligning hole located alongthe centerline of the said shank and adapted to receive the aligningpin.
 5. A tennis racket assembly comprising a string-frame supportincluding a shank, a handle grip at one end of said shank, and agenerally oval racket frame at the other end of said shank, said racketframe being bifurcated along approximately the one-half portion thereofremote from said shank to form a slot and formed with an inwardly facingchannel in alignment with said slot along the remaining portion thereof,an aligning hole defined in said racket frame adjacent said shank, agenerally oval string frame generally of a size and shape correspondingto the size and shape of said racket frame and of a thickness sufficientto be snugly received in the slot and channel of said racket frame, saidstring frame being of smaller width in the portion thereof adjacent saidshank and including outwardly extending shoulders at the junction of theslot and channel of said racket frame, said string frame including analigning peg projecting therefrom and received in the aligning hole ofsaid racket frame, and fastening means positioned at the end of saidracket frame remote from said shank for clamping said racket frameagainst said string frame.